The whole purpose of the gospel is to deliver us from the slavery that Adam and his race brought man into. Jesus came to demonstrate on earth how God originally wanted Adam to live.
If the devil cannot outrightly deceive you because of your strong Christian convictions, he will try to sidetrack you. There are many ways the devil sidetracks Christians, for example: make you get involved / engaged with with some other(seemingly good) things which God has not instructed you to do.
John 8:32 says if you know the truth, it shall set you free.
This means that the more truth you know, the more free you become. If something is the truth, it will set me free. If something is the truth, it will set you free. If it doesnt set you free, it can’t be the truth. If it brings you into bondage, condemnation, discouragement, depression, that cannot be the truth or else you didn’t understand it correctly.
Free? Free from what? Jesus, in John 8:32 primarily spoke about freedom from sin. But don’t forget that a lot of sin men(and women) commit is a result of customs and traditions that are contrary to the word of God.
Free? Yes, freedom from the opinions of men; freedom from seeking to please men; freedom from gloom, depression and discouragement; the kind of things Jesus was free from. The more you know truth, the more free you become. The more of truth that you know, the more free you become. If you want to test whether you are really free, check yourself if you are really free from those things Jesus Christ was free from when he was on earth..